1. Cross References
The present application is related to the co-pending application of Dean C. Puzzo entitled "Transmission Signal Direction Finding Apparatus and Method", filed on even date herewith.
2. Field of the Invention
This invention generally relates to the instantaneous measurement of signal frequencies and particularly to apparatuses and methods for instantaneous frequency measurement which are capable of operation when more than one signal is simultaneously present.
3. Statement of the Prior Art
Devices for the instantaneous measurement of signal frequencies, IFMs, have been known and used for some time. Unfortunately, such devices are limited in their measurement ability when more than one signal frequency is present. When two signal frequencies are present and their respective signal powers are within (6) dB of each other, an IFM generally cannot measure the frequency of either signal. When two signal frequencies are present and their respective signal powers differ by more than (6) dB, an IFM can measure the frequency of the higher power signal but cannot measure the frequency of the lower power signal.